Transient Correction Using EDFA: In-Line Optical Fiber with Feedback

The advent of EDFA in late 1980s was one of the major events in the history of optical communication. It provided new life to the optical fiber transmission window centred at 1.55 µm and the consequent research into technologies that allow high bit-rate transmission over long distances. EDFAs have high gain, operating at low pump power and their performances are better in comparison with other similar amplifiers and optical devices. Also, the EDFAs have large bandwidth, a low noise figure and polarization insensitivity. However, in case of EDFA based WDM systems a serious problem of transients is observed. This problem can be rectified using several methods. The methods like addition of channels, different modulation formats and using compact EDFAs. Here the implementations for EDFA based WDM Transmission system using various topologies have been proposed and then multiple simulations were carried out to obtain proper Gain Flattening in the Transmission System. In addition to this a detailed analysis has been carried out to compare the Gain Flattening capabilities of various implemented topologies. The results obtained were in well accordance with the practical results.